Mercedes-Benz Sprinter 2003 Manual page 83

CIRC PUMP CONTROL SHORTED —
TEST
2 WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA
THAT DOES NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS
VENT THE EXHAUST WHEN OPERATING THE HEATER. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY
OR DEATH.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater harness connector.
Remove the substitute Circulation Pump Relay from the relay center.
Measure the resistance between ground and the Circulation Pump Relay High Side
Control circuit.
Is the resistance below 10K ohms?
Yes → Repair the Circulation Pump Relay High Side Control circuit for
→ Go To 3
No
3 WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA
THAT DOES NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS
VENT THE EXHAUST WHEN OPERATING THE HEATER. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY
OR DEATH.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater harness connector.
Remove the Circulation Pump Relay from the relay center.
Measure the resistance between the Circulation Pump Relay High Side Control
circuit and the Ground circuit (Circulation Pump Relay connector terminal 86 and
85).
Is the resistance below 10K ohms?
Yes → Repair the Circulation Pump Relay High Side Control circuit for
→ Replace the Cabin Heater Assembly in accordance with the
No
ACTION
a short to ground. Reinstall the original Circulation Pump Relay.
Perform HEATER VERIFICATION TEST - VER 1.
a short to the Ground circuit.
Perform HEATER VERIFICATION TEST - VER 1.
Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
Continued
75
CABIN HEATER
APPLICABILITY
All
All